Our aim is to continue to apply resonance Raman spectroscopy to probe the molecular basis of visual excitation. We plan to complete our investigations of the thermal intermediates using photostationary mixtures at low temperatures with UV as well as visible lasers. We have also devised a new technique to obtain pure kinetic intermediates. This new double beam flow technique should overcome the problems we have encountered in obtaining spectra of lumirhodopsin. We also hope to focus our attention specifically on elucidating the structure of bathorhodopsin. The spectrum of bathorhodopsin can be obtained at 77K by a procedure that deconvolutes the batho bands from the spectrum of the photostationary mixture. We have found, however, that this procedure does not give the detail necessary for accurate modeling. Therefore we have devised a new picosecond technique that is capable of obtaining the spectrum of pure bathorhodopsin at room temperature. To aid in our modeling procedure we will study synthetic visual pigment analogs. These investigations should play an important role in our efforts to understand the structure and interactions that are responsible for producing and stabilizing bathorhodopsin and other thermal intermediates. The conformational analysis that is an essential part of our experiments will be based on a continuing series of model system studies to characterize the ground state vibrational frequencies and the role of the excited state in the intensities observed in the groundstate spectrum. Finally, we hope to analyze kinetically all the intermediates using kinetic resonance Raman spectroscopy. As we have recently shown, kinetic resonance Raman spectroscopy is a powerful technique that can follow kinetic transformations in local regions of the retinylidene chromophore. These experiments should transform the normally static resonance Raman spectra into a powerful probe of local dynamic changes in the retinylidene chromophore.